Free ranging is great, and you will have losses, sometimes one, sometimes everyone.

As a comparison, I have my chickens in an enclosed chicken run with bird netting on top. No losses in the year and a half I have had my chickens. The chicken run is not predator proof, but it is predator resistant. On the other hand, locals that have let their chickens free range often have no flock left by fall. Almost guaranteed to suffer some loss and perhaps lose the whole flock by free ranging where I live.
Once my hens are beyond their egg production years, I may retire them to a different coop with free range freedom. That is what some people do around here instead of culling the older hens. Still would have to feed them in winter where I live. But maybe that's OK as they deserve some retirement benefits in their old age.